[Boost-build] Conditional features do not work in variant definitions.

Subject: [Boost-build] Conditional features do not work in variant definitions.
From: Ivan Tkatchev (itkachev_at_[hidden])
Date: 2012-11-20 06:23:22

Here's a simple example:

   variant mybuild : release :
     <debug-symbols>on
     <toolset-gcc:version>mygcc:<library>/lib/something.a
   ;

   project myapp :
     requirements
     <threading>multi
   : default-build mybuild ;

This fails with an error, complaining that "mygcc:<library>/lib/something.a" is 
not a valid gcc version.

If I change this to the following:

   variant mybuild : release :
     <debug-symbols>on
   ;

   project myapp :
     requirements
     <threading>multi
     <toolset-gcc:version>mygcc:<library>/lib/something.a
   : default-build mybuild;

For some reason conditional features do not work when used in a build variant 
definition.

Any reason for this behaviour, and is there a fix?

Thank you.